Sound-reproducing machine



' March 6, 1928.

\ I V 5 I I W. H. THOMMEN SOUND REPRODUCING MAOHIBE Filed Sept. 27. 1920 INVERPTIZHK- ATT 1:1 RNEY.

Patented Mar. 6, 1928.

WILLIAM Hi rnommnn, or PLYMOUTH, WISCONSIN.

sonnn-nnruonncrne MACHINE.

Application filed September 27, 1920. Serial No. 413,111.

This invention relates in general to in'1- provements is the art of reproducing sound, and relates more specifically to improve ments in the construction and operation 6 of sound reproducing machines such as phonographs, which are capable of reproduci g sound-s simulative of the huinan' voice, in-

strumental i'nusic and the like.

A general object of the invention is to pro- 10 vide a sound reproducing machine which is simple in its construction and etiicient in op eration. Another general object of the invention is to provide a combined phonograph and article of furniture, which will most effectively serve both purpo:

In the resent. commercial phon'ographs which are especially designed to permit secondary Utilization thereof an article of furniture such as a pedestal or a table, the utility of the devices for such. secondary purpose is considerably diminish d beca rse of the fact that the sound reproducing mechanisms are made acces-sibletor manipulation, through the tops of the cabinets lifting oi. otherwise removing top covers. With such prior devices it is necessary in orderrto manipulate the reproducing mechanism, to remove or otherwise disturb objects resting upon the top of the cabinet, and in most 30 cases it is further necessary to raise and lower a relatively cumbersome top cover.

It is further desirable in order to secure most efficient amplification of sound wayes, to provide an amplifying chamber which is relatively voluminous. it being preferable to have the amplifying chamber as longas possible and of relatively large gradually in creasing cross-sectional area. In the present connnercial cabinet machines, the amplifying chamber communicates with the rear portion of the tone arm and eirtends forwardly toward the front of the cabinet below the reproducing niec'hanisn'n In such machines the length of the amplifying chant-- her is ordinarily limited by the depth of the cabinet, and the cross-sectional area of this chamber is limited by the space required for the storage of records, the space required to house the driving motor. and the space surrounding the reproducing mechanism, each of these elements being housed Within a separate compartment, independent of the sound amplifying chamber. As it is costly and otherwise undesirable to. increase the size of the cabinet merely inorder to secure increased volume in the amplifying chamber,

the sound amplifying chambers of most of the present comn'icrcial machines are ineiiicient in construction. It is also a' fact that considerable space such as the reproducing mechanism housing space which might be utilized as a sound amplifying chamber, is Wasted in the present cabinet machines.

Another objection to the present commercial cabinet machines, is that the sound is delivered therefrom only through restricted passages or openings in one of the four walls of the cabinet, usually the front wall. Vitli such an arrangement the entire sound of necessity delivered in one direction only, and when a machine of this character is operated in large halls or in the open air, the sound is muflied, improperly distributed, and cannot be heard l'or any appreciable distance.

The present invention contemplates provision of a sound reproducing machii'i'e which obviates these detects ot' the prior art machines by permitting effective utilization thereof as an article of furniture, by providing a relatively large and eliicient amplifying chamber Without necessitating appreciable increase in the size of the cabinet, and by providing for effective delivery of the sound from various portions of the cabinet. The cabinet of a machine constructed in accordance with the present invention has its top iminovably associated with the side walls thereof. With the present invention the amplifying chamber is combined with the chamber for housing the sound reproducing mechanism. A machine embodying the present invention is provided with means for etfectively guiding, distrilmting and deliveringthe sound leaving the an'iplitying chamber. from the trout and side walls of the cabinet. The invent-ion is applicable either to the ordinary cabinet phonograph or to a phonograph of the table type, and provides an exceedingly simple, compact and highly eflicient sound reproducing machine which may be manufactured at moderate cost.

These and other objects of the present invention and the manner of their accomplishment, will become apparent in the course of the following description. A clear conception of an embodiment of the invention and of the operation of a device constructed in accordance therewith, may be had by referring" to the drawing accompanying and forming a part of this specification, in which like reference characters designate the same or similar parts in the several views.

Fig. 1 is a side elevation, partly in section, of a. sound reproducing machine of the cabinet type.

Fig. 2 is a front view of a sound reproducing machine of the cabinet type, the upper front door having been omitted therefrom and the side walls of the amplifying chamber having been slightly displaced.

Fig. 3 is a transverse horizontal section through a sound reproducing machine of the cabinet type, the section being taken along the irregular line III1I1 of Fig. 1 looking in a downward direction.

The sound reproducing machine disclosed in the drawing, comprises in general a casing 10, sound reproducing mechanism located within the upper portion of the easing, a motor for actuating the mechanism located within a medial portion of the casing, an amplifying chamber 8 located in direct proximity to the sound reproducing mechanism, and a record storage chamber located within the lower portion of the easing 10.

The cabinet or casing 10 consists of four rigidly connected corner standards or posts 11 to the upper extremities of which the cabinet top 122 is immovably attached, and the lower extremities of which are formed as supporting legs. The side walls, back, and bottom of the cabinet are also immovably attached to the posts 11, and a stationary motor supporting board 17 divides the interior of the casing 10 into two superimposed main chambers. The actuating motor which has been omitted from the disclosure. is preferably secured to the under side of the motor board 17 in any suitable manner and is housed within a supplementary compartment located directly below the board 17 and above the record storage space. The driving or actuating motor is ordinarily of the spring type. capable of being energized by means of a winding crank 15 at the side of the cabinet, and adapted to deliver rotary motion to a vertical main spindle l-l. An electric motor may also be employed, in which event the crank 1.") is omitted. Access to the record storage chamber or space which is located in the lower portion of the casing 10, may be had through a front door 16.

The sound reproducing mechanism consists of a rotary horizontal turn table 2 detachably associated with the upper extremity of the spindle 1% and adapted to support a disc record -ll, a reproducer 3 having a stylus and needle adapted to coact with a spiral groove formed in the record 4, and a horizontally oscillatory tone arm 5 movable over the record 4: and supporting the reproduccr 3. The tone arm is provided with an interior passage or conduit for conducting the sound waves produced by the reproducer 3, in condensed form, to a rear amplifying chamber (3. The rear am 'ilifying chamber (3 rapidly but gradually enlarges in cross-sectional area, the smaller cud of this chamber communicating with the tone arm 5 and the larger end thereof communicating with the main upper an'iplifying chamber 8. The main amplifying chamber 8 extends forwardly and laterally over and in direct proximity to the sound reproduc ing mechanism, being also formed with gradually increasing cross-sectional area.

The bottom of the combined amplifying and reproducer housing chamber 8, is bounded by the motor board 17, while the top and rear thereof are bounded by walls having three gradually curved upwardly inclined surfaces 123, 2;) extending forwardly and laterally, respectively relatively to the casing 10, as shown in Figs. 1 and 2. The lower extremities of these guiding surfaces 13, 23 of the bounding walls mcet just above the auxiliary amplifying chamber (3, to form a depending splitter or distributor for the sound waves delivered upwardly from the chamber (3. The main amplifying chamber 8 has a front and two side delivery openings which communicate with openings in the front grille or door 7 and in the opposite side grilles 9, respectively. These grille openings are ordinarily covered with sill: or other line meshed fabric for preventing dust from entering the amplifying chamber 8. The front grille or door 7 is preferably hinged so as to permit ready access to the amplifying chamber 8 for manipulation of the sound rc 'iroducing mechanism. The side grilles 9 may also be made removable to permit free access to all portions of the ainpli fying chamber 8.

During the normal operation of the machine, a disc record l is located upon the turn table 2, the reproducer 3 and tone arm 5 are positioned as shown. and the driving motor is released to impart rotary motion to the record t and turntable 2 through the vertical main spindle lei. As the record t revolves, the needle of the rcproduccr 1-, is vibrated by undulations on the record thread. these vibrations of the needle being imparted to the reproducer diaphragm which produces sound waves. The condensed sound waves thus produced are delivered through the interior passage of the tone arm 5 to the auxiliary au'iplifving chamber (3. In the chamber (3 the direction of travel of the sound waves is reversed and the waves are sinmltaneously partially anipliiicd. the successive amplilicd waves being delivered upwardly into the throat of the main amplifying chamber 8 and against the splitter therein. The sound waves are then successively delivered through and further gradually amplified in the chamber 8, being eventually delivered in finally amplified form from the casing 10 through the openings in the front door 7 and side grilles 9. Due to the spiral formation of the groove in the disc record 4, the tone arm 5 and reproducer 3 are gradually swung horizontally over and toward the center of the record, until the, inner end of the recording thread is reached, when the motion of the driving motor and the associated parts may be arrested either by manually applying a brake or by means of an automatic stop of suitable construction. lVhile the reproducer 3 and disc record 4 disclosedin the drawings are of the form known in the art as lateral undulation reproducing mechanism, it will be obvious that the present invention is also applicable to machines utilizing hill and dale and other forms of recording mech anisms.

If it is desired to change a record 4 or to otherwise manipulate or inspect the sound reproducing mechanism, access to the mechanism is readily had by opening the front door 7 without disturbing objects located upon the stationary top 12 of the cabinet. With this arrangement and disposition of the elements, the top 12 may be readily utilized to support any desired object or decoration, ormay be employed as a convenient support for the record album from which a record has been temporarily removed for reproduction. If a greater range of access to the amplifying chamber is desired, the side grilles 9 may also be removed thereby fully opening three sides of the chamber 8.

From the foregoinw description it will be noted that a desirably long and gradually enlarging efiicient amplifying chamber for the sound waves, is provided without materially increasing the size of the cabinet or casing 10. It is found that the disposition of the reproducing mechanism within the amplifying chamber 8 does not undesirably aifect the acoustic nature of delicate sounds, such disposition permit-ting combination of the amplifying and rcproducer housing chambers and producing a relatively compact structure.

It will also be observed that the throat of the amplifying chamber 8 is formed to simulate the structure of the human throat which is known to be a highly efficient sound distributor and amplifier. By providing exit openings for the amplified waves on three sides of the cabinet, the sound may be effectively distributed by the wall surfaces 13, 23 and delivered over a relatively great area. If it is desired to limit the distribution to one or more of the three normal directions of delivery, some of the grille openings may be closed to produce the desired result. The features of the invention are readily applicable to the table type of cabinet as well as to other forms,.to produce the desired advantageous results;

It should be understood that it is not desired to limit the invention by the use of specific terms or otherwise, to the exact details of construction and operation herein shown and described, for various modifications within the scope of the appended claims, may occur to persons skilled in the art,

it is claimed and desired to secure by Letters Patent 1.- In combination, means for producing sound waves, a tone arm for conducting sound waves rearwardly away from said means and for initially amplifying said waves, means forming an initial amplifying chamber communicating with said tone arm, and means forming a single final amplifying and distributing chamber communicating directly with the delivery end of said initial amplifying chamber, said final amplifying chamber being open at the front and both sides and being bounded at the top and rear by a forwardly and two laterally and up *ardly inclined intersecting surfaces for conducting sound waves delivered from said tone arm and from said initial amplifying chamber in forward and lateral directions.

2. In combination, means for producing sound waves, a tone arm for conducting sound waves reai'wardly away from said means and for initially amplifying said waves, means forming an initial amplifying chamber communicating with said tone arm, and means forming a single final amplifying and distributing chamber communicating directly with the delivery end of said initial amplifying chamber, said final amplifying chamber being open at the front and both sides and being bounded at the top and rear by forwardly and two laterally and upwardly inclined intersect-ing surfaces having rectilineal horizontal generatrices for conducting sound waves delivered from said tone arm and from said initial amplifying chamber in forward and lateral directions.

3. In combination, means for producing sound waves, a tone arm for conducting sound waves rearwardly away from said means and for initially amplifying said waves, means forming an initial amplifying chamber communicating with said tone arm, and means forming a single final amplifying and distributing chamber communicating directly with the delivery end of said initial amplifying chamber, said final amplifying chamber being open at the front and both sides and being bounded at the top and rear by a forwardly and two laterally and upwardly inclined intersecting surfaces curved in the direction of their inclination for conducting sound waves delivered from being bounded at the top and rear by a forwardly and two laterally and upwardly inclined intersecting surfaces for conducting sound waves delivered from said tone arm and from said initial amplifying chamber in forward and lateral directions, said sound wave producing means being freely accessible for manipulation through the front and side delivery openings of said final amplifying chamber.

in testimony whereof, the signature of the inventor is allixed hereto.

\VILLIAM H. THOMMEN. 

